The chrysanthemum (Dendranthema grandiflora Tzvelev.) cultivars `Dark Charm', `Salmon Charm', `Coral Charm' and `Dark Bronze Charm' are either radiation-induced mutants or spontaneous sports of `Charm' and constitute a family or series of plants that primarily differ in flower color. These cultivars, which were difficult to differentiate genetically by DNA amplification fingerprinting (DAF), were easily identified by using arbitrary signatures from amplification profiles (ASAP). Genomic DNA was first amplified with three standard octamer arbitrary primers, all of which produced monomorphic profiles. Products from each of these DNA fingerprints were subsequently reamplified using four minihairpin decamer primers. The 12 primer combinations produced signatures containing ≈37% polymorphic character loci, which were used to estimate genetic relationships between cultivars. Forty-six (32%) unique amplification products were associated with individual cultivars. The number of ASAP polymorphisms detected provided an estimate of the mutation rate in the mutant cultivars, ranging from 0.03% to 1.6% of nucleotide changes within an average of 18 kb of arbitrary amplified DAF sequence. The ASAP technique permits the clear genetic identification of somatic mutants and radiation-induced sports that are genetically highly homogeneous and should facilitate marker assisted breeding and protection of plant breeders rights of varieties or cultivars.
Four chrysanthemum (Dendranthema grandiflora) spontaneous and radiation-induced sports from the cultivar `Charm' and phenotypically differing only in flower color were individually characterized using arbitrary signatures from amplification profiles (ASAP). ASAP analysis is based on a two-step arbitrary primer amplification procedure that produces “fi ngerprints of fingerprints.” In the first step, `Charm', `Dark Charm', `Dark Bronze Charm', `Salmon Charm', and `Coral Charm' were fingerprinted by DNA amplification fingerprinting (DAF) with standard octamer arbitrary primers. Diluted products from three monomorphic fingerprints for each cultivar were subsequently reamplified using four minihairpin decamer primers. Each of the 12 ASAP profiles revealed polymorphic loci that were used to uniquely identify cultivars and estimate genetic relationships. The ASAP technique permits identification of previously genetically indistinguishable plant material and should facilitate marker assisted breeding and protection of ownership rights.
Four chrysanthemum (Dendranthema grandiflora) spontaneous and radiation-induced sports from the cultivar `Charm' and phenotypically differing only in flower color were individually characterized using arbitrary signatures from amplification profiles (ASAP). ASAP analysis is based on a two-step arbitrary primer amplification procedure that produces “fingerprints of fingerprints.” In the first step, `Charm', `Dark Charm', `Dark Bronze Charm', `Salmon Charm', and `Coral Charm' were fingerprinted by DNA amplification fingerprinting (DAF) with standard octamer arbitrary primers. Diluted products from three monomorphic fingerprints for each cultivar were subsequently reamplified using four minihairpin decamer primers. Each of the 12 ASAP profiles revealed about 30% polymorphic loci and some were used to uniquely identify cultivars and estimate genetic relationships. The ASAP technique permits identification of previously genetically indistinguishable plant material and should facilitate marker assisted breeding and protection of ownership rights.
somatic mutants ( Capo-chichi et al., 2005 ; Harris-Shultz et al., 2010 ; Wang et al., 2010 ). Although many cultivars have been derived from ‘Tifgreen’ and ‘Tifdwarf’, most mutations are deleterious. Inconsistencies in appearance, playability, response
factors that control fruit size and to elucidate the physiological changes caused by changes in the fruit size. The weight of persimmon ( Diospyros kaki Thunb.) fruit ranges from less than 60 g to more than 300 g depending on the cultivar. Somatic or
germplasm with ‘Green Matalon’ and ‘Black Matalon’ ( Bandelj et al., 2008 ). Skin color distinction can result from somatic mutation arising during intensive propagation by cuttings as shown in the grape cultivars Pinot noir and Pinot blanc ( Hocquigny et al
Abstract
Eleven suspected somatic mutations, consisting of 7 trees and 4 individual branches of the ‘Montmorency’ cherry, were compared with standard ‘Montmorency’ for phenotypic traits including tree height, trunk circumference, leaf area, crotch angle, resistance of flowers to frost injury, pollen germination, fruit set, individual fruit weight, fruit removal force, and yield. Differences occurred between some variants and ‘Montmorency’ controls for all characters except fruit removal force. All variants were tetraploid (2n = 32), as is standard ‘Montmorency’, with no evidence of cytochimerism.
Somatic sectors possessing mutations affecting flower and fruit development were found at a high frequency in an F4 tomato plot. Over the past 4 years, this population has manifested a range of variant phenotypes, including conversion of calyx to leaflets; flecking, striping of sectoring of fruit; and development of “prolific callus” (PC) fruit, characterized by the green fruit bursting open, with new flowering shoots developing from the internal tissue. The variant phenotypes were not stably inherited. The majority of plants having sectors with abnormal flowers, abnormal fruit, or PC fruit developed phenotypically distinct somatic sectors. The aberrant phenotype ratios, the very high frequency of somatic reversions toward normal development, and the range of traits affecting tomato reproductive development indicate this could involve a transposable element interacting with control genes involved in tomato reproduction, with the phenotype partly dependent on the timing of the transposition event.
Somatic mutations in shoot growing points, while considered relatively common in many horticultural clones, cannot be detected unless the mutation results in a distinguishable change and comes to occupy sufficient shoot area to be observable. Noninfectious bud-failure (BF) in almond, a genetic mutation which results in failure during early development of vegetative but not flower buds, behaves as a chimera in its incidence within an affected tree and in vegetative progeny from bud-failure prone clonal sources (i.e., vegetative lineage). Early stages of BF development are thought to occur as very limited and so undetected sectorial or mericlinal chimeras. Detection of BF during these early stages would be very valuable for the selection of low-BF source clones for nursery increase. Flower symmetry, as measured by differences in the size of each of the five petals of an almond flower, was evaluated as an indicator of the relative fitness of the individual cell lineages from which different petals were derived. Several hundred flowers from individual clonal sources of the almond variety `Nonpareil', known to produce either very low, medium, or very high levels of BF in their vegetative progeny, were tested over 3 separate years. Significant reductions in flower symmetry were consistently observed for medium BF potential clonal sources relative to either low- or high-BF sources despite the lack of any observable BF symptoms in the medium-BF trees tested. Associated with asymmetric-flower-prone sources was a greater number of an easily distinguishable distorted petal morphology. Medium BF-potential sources consistently produced 2- to 3-fold greater numbers of this petal morphology relative to low BF-sources, although the occurrence of distorted petals in both low and medium BF sources limits its use as an efficient field selection tool. Research findings, however, are allowing a more detailed understanding of the developmental ontogeny of “bud-sport” mutations and may have application in the analysis of otherwise hidden chimeras resulting from either somatic mutations or genetic transformation/regeneration schemes.
A crumbly fruited clone of `Centennial' red raspberry (Rubus idaeus L.) had fewer drupelets per fruit and smaller fruit than normal-fruited `Centennial'. Although there was more abortive pollen in the crumbly clone of `Centennial', there was no difference in drupelet set between the two `Centennial' clones when used as paternal parents. Thus, in `Centennial', the mechanism causing crumbly fruit was primarily a maternal effect. There was no evidence of disease as a cause of the crumbly fruited `Centennial' clone and observations were consistent with a somatic mutation.